A large number of novel, herbicidally active compounds have been prepared in the past years, which could be used pre-emergence and/or post-emergence.
The derivatives of 2-(heteroaryloxy-phenoxy)propionic acid are of great importance due to their highgrade selectivity, whereby they can be used with a highdegree safety for killing (controlling) annual and perennial monocotyledonous weeds in dicotyledonous cultures.
These compounds possess a relatively high translocation ability in the plant; they induce necrosis or chlorosis in the tissues of the meristem and developing leaves of sensitive plants. Via an accompanying biochemical effect, they increase the membrane-permeability and inhibit the auxin-induced reactions (hypoauxinosis). Their inhibitory effect on the de novo fatty acid biosynthesis bears the same importance in their activity as their auxin deficiency-inducing effect [Walker et al.: Biochem. J. 254, 811 (1988)].